HONG KONG, Oct 9 (Reuters) - Hong Kong leader Carrie Lam on Tuesday would not explain why authorities rejected a work visa renewal for a prominent British journalist, in an unprecedented case that has tarnished the city’s international reputation and stoked outrage.

Victor Mallet, the Asia editor for the Financial Times newspaper, who has been based in Hong Kong for the past two years, was told last week his work visa would not be renewed.

Two months ago, Mallet hosted a luncheon speech at the Hong Kong Foreign Correspondents Club (FCC) by an independence activist, Andy Chan, that Chinese and Hong Kong officials strongly criticised.

Zhang Xiaoming, the head of Beijing’s Hong Kong and Macau Affairs Office, told reporters at the time that the FCC had broken the law by hosting a “separatist” and was in effect aiding separatism.

The FCC, one of Asia’s leading press clubs, which has hosted Chinese and Hong Kong officials among other prominent speakers, said that it neither endorsed nor opposed presenters’ views, but that it was an institution that champions free speech.

Hong Kong’s leader Carrie Lam, however, addressing the controversy directly for the first time, skirted questions on whether Mallet was being punished for hosting the Chan speech.

“What you said is pure speculation,” she told reporters.

But she declined to explain why Mallet has been effectively forced to leave the city. She reiterated comments by other senior Hong Kong officials that authorities wouldn’t comment on an individual visa, and that the decision was made in accordance with the law and the specific circumstances of the case.

Hong Kong, a former British colony, reverted to Chinese rule in 1997 amid guarantees the global financial hub would enjoy a high degree of autonomy and freedoms under a “one country, two systems” formula.

Critics say Hong Kong’s rights landscape has deteriorated in recent years amid a spate of controversies, including the jailing of young activists and disqualifications of pro-democracy lawmakers from the legislature.

Lam would not offer specifics on whether other journalists would face repercussions for reporting on the topic of independence or speaking with independence activists.

“I’m sorry, I cannot tell you exactly how journalists should say, or act, or interview, but I can assure you ... freedom of expression, freedom of reporting, are core values in Hong Kong.”

Mallet, who is in Hong Kong on a tourist visa that expires on Sunday, thanked all those who have supported him, including journalists, lawyers and citizens.

An online petition calling for authorities to reverse their decision and allow the seasoned journalist to work in the city again has drawn more than 10,000 signatures.

“I am very grateful to all those who have signed this petition, particularly those from Hong Kong, which has been home to our family for a total of more than 7 years,” he wrote on Facebook. (Reporting by James Pomfret; Editing by Gerry Doyle)